Synchronizing system



2 Sheets-Sheet 1 alle: MJ/L,

Dec. 8, 1942. H. MYERS SYNCHRONIZING SYSTEM Filed oct. 25, 1941 2sheets-sheet 2 ,Herwig/@enr www Patented Dec. 8, 1942 UNITED STATESPATENT OFFICE SYNCHRONIZING SYSTEM Henry Myers, Colonie, N. Y.

Application October 23, 1941, Serial No. 416,265

12 Claims.

This invention is related to means for maintaining synchronism betweenrevolvable motor means at a transmitting station and revolvable motormeans at a distant receiving station.

It is an` object of this invention to maintain a revolvable element at adistant receiving station in phase with a revolvable element at atransmitting station.

It is a further object of this invention to provide means formaintaining revolvable elements at spaced apart radio transmitting andradio receiving stations, respectively, in phase with each other.

Other and further objects and advantages of my invention will -beapparent from the follow-` ing description taken in connection with theaccompanying drawings.

In the drawings:

Figure 1 shows diagrammatically the means forI normally transmitting asustained radio carrier and means for momentarily and at regular timeintervals modulating the carrier at audio frequencies;

Figure 2 shows diagrammatically means at a radio receiving station forcontrolling the phase position of a revolving element in response to thereception of a modulated radio carrier;

Figures 3 and 4 are descriptive diagrams of the method of controllingthe phase position of the revolving element at the receiving station;and

. Figure 5 is a diagrammatic showing of a modication of the controllingmeans of Figure 2.

In Figures 1 and 2 there are shown a sending station and a receivingstation, respectively, which includes motor-driven elements to bemaintained in phase with each other by means described hereinafter.

A conventional radio transmitter I is suitably connected to an antenna II, and the carrier is modulated by a conventional modulator I2,connected to the transmitter to modulate the carrier at audiofrequencies in a manner well understood in the radio art.

I'he modulating means comprises a microphone I3 connected to themodulator in a conventional manner, and the microphone is actuated bysound waves from a conventional buzzer I4 placed adjacent thereto. Thebuzzer is energized by a battery I5 connected by wires I6 and I1 inseries with a switch I8 actuated by a cam indicated generally at C1.

The modulator and the transmitter are connected to a source of power,indicated at I9, by wires and 2l, in series with a switch 22.

An electric motor 23 of the conventional shunt type is connected to asource of power, indicated at 24, by wires 25 and 26, in series with anormally closed switch 2l, and this motor drives a cam 28 to actuate theswitch I8.

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It is convenient to consider the cam 28 as a disk having a projection29, engageable with a follower 3D on the arm of the switch I8.

It will now be obvious that when the switch 22 is closed to energize thetransmitter a carrier will be emitted by the antenna II, and that whenthe motor 23 is rotating, following the closing of the switch 2l, theswitch I8 will be closed once per revolution of the disk 28 tomomentarily actuate the buzzer I4 and so modulate the output of thetransmitter at audio frequencies.

The microphone and buzzer have been shown for the ready illustration ofmeans to modulate the carrier at audio frequencies, but it is obviousIthat other means may be employed to modulate the carrier at audiofrequencies in response to the closing of the switch I8, and that themeans shown are for illustration and not by way of limitation.

At the receiving station, shown in Figure 2, the carrier is received byan antenna 3l connected to a conventional receiving set employingelectron tubes, and this set comprises a conventional tuned detector,indicated at 32, and a conventional amplii'ler, indicated at 33, and thereceiving set includes the usual power sources (not shown).

The output circuit of the amplifier 33 is connected by wires 34 and 35to the coil 36 of a relay 3l. The relay 3l includes an armature 38 and acontact 39 to form a switch to close a circuit including a battery 40,wires 4I and 42, and the coil 43 of a latching relay 44.

'I'he relay 3l is adjusted, in cooperation with the detector andamplifier, so that its armature moves to circuit-closing position onlywhile the carrier is modulated upon the closing of the switch IB at thesending station.

When the sending and receiving stations are a moderate distance apart,the relay 3'I is normally biased towards closing by the direct currentoutput of the receiving set while the unmodulated carrier is beingreceived.

The latching relay 44 includes an armature 45 as a latch to normallyretain an arm 46 of a switch 4l seated thereon, and to release the arm46 for movement to circuit-closing position when the relay 44 isenergized.

A conventional shunt type electric motor 48 is suitably connected to apower source indicated at 49 through a normally closed switch 50 andwires 5I and 52.

The motor drives a cam, indicated generally at C2, and which comprises adisk 53 having a projection 54 engageable with a follower 55 on the arm46, so that the cam may raise the switch arm 46 to be latched by thelatch 45.

When the switch 4l is open, with the arm 46 flatched, current ilow tothe motor is from the source, through the motor armature, through aresistor 55, and through Wire 52, so that the motor runs at reducedspeed because of the insertion of the resistor in the armature circuit.When the switch 41 is closed, it shunts the resistor 55 through the arm46, contact 51, and wires 58 and 59, so that the motor now runs atnormal speed.

It will now be obvious that the momentary reception of the modulatedcarrier results in the actuation of the latching relay 44 to release theswitch arm 46 to cause the motor to run at normal speed, provided thatthe arm 46 has been latched, and that the cam C2 will, once perrevolution, open the switch 41 to reduce the speed of the motor if theswitch 41 is closed.

Figures 3 and 4 are employed in connection with what follows to describehow the disks 23 and 53 are held in phase.

Referring to Figure 3, the time interval between signals is thatrequired to complete a cycle and is denoted by T. The time required forthe disk 53 to make a complete cycle at reduced speed is ts, and that tomake a complete cycle at normal speed is tf.

When the disk 53 is in phase with the disk 28, then :c-l-y=l, andT=ts1ytf, where :v and T are given the values desired. A Value of if isselected, and a value of ts is then calculated. o: and y are fractionalparts of a complete cycle.

Referring now to Figure 4, if the cam 53 is out of phase when the signalis received, as indicated at C1, then The values T, ts, and tf have beenselected for that value of :c which places the cam in the desired phaserelation. The values of :r and y will change in each time interval Tuntil .r reaches the predetermined value for phase position, and :v willthereafter retain that value even if the projection 54 reaches thefollower 55 at the same instant, immediately before, or immediatelyafter the signal arrives.

A modified form of the motor control means at the receiving station isshown in Figure 5. Similar numerals have been employed to indicate partssimilar to those shown in Figure 2. The relay 31, responsive to themodulated carrier, momentarily closes a circuit which comprises abattery ED and wires 5| and 62 to energize relays 63 and E4, and relay63 closes to form a holding circuit comprising the battery 65, wires 6iand 65, and the cam-operated switch B5, so that if the switch 65 isclosed, then the relay 64 is held closed to close its switch 61 to shuntthe resistor 55 in series with the armature of the motor 48.

When the switch G5 is opened, once per revolution, by the projection 54engaging the follower 55, the holding circuit is broken, and the relay64 becomes deenergized so that its switch 51 opens to again insert theresistance 56 in series with. the armature of the motor 43. Thus, therelays 63 and 64 function to normally shunt the resistor after beingonce energized, and to insert the resistor when the switch 66 opensuntil they are again energized by the modulated carrier with the switchE5 closed. The modification shown in Figure 5, therefore, functions toobtain the result of the circuit arrangement of Figure 2.

According to the provisions of the patent statutes, I have set forth theprinciple and mode of operation of my invention and have illustrated anddescribed what I now consider to represent its best embodiments,However, I desire to have it understood that Within the scope of theappended claims the invention may be practiced otherwise than asspecifically illustrated and described.

I claim as my invention:

1. synchronizing means comprising radio transmitting means to transmit anormally sustained carrier, means momentarily actuatable at regular timeintervals to modulate said carrier, a motor, a source of currentconnected to said motor, a resistor, means actuatable by said motor toinsert said resistor in series with said source to reduce the speed ofthe motor, and means responsive to the modulating of said carrier toshunt said resistor to thereby cause the` motor to run at apredetermined normal speed.

2. synchronizing means comprising radio transmitting means to transmit anormally sustained carrier, means momentarily actuatable at regular timeintervals to modulate said carrier, a motor, a source of currentconnected to said motor, a resistor in series with said source, a switchincluding an element movable to closed position to shunt said resistorand thereby cause said motor to run at a predeterminedA normal speed,means driven by said motor to open said switch and thereby cause saidmotor to run at a reduced speed, relay means to latch said element inopen position, and means including said relay means responsive to themodulating of said carrier to release said element for movement toclosed position,

3. synchronizing means comprising transmitting means to transmit anormally sustained carrier, means momentarily actuatable at regular timeintervals to modulate said carrier, a motor, a source of currentconnected to said motor, a resistor in series with said source, switchmeans closable to shunt said resistor and thereby cause said motor torun at a predetermined normal speed, means actuatable by said motor toeffect opening of said switch and thereby C cause said mo-tor to run ata reduced speed, and

means responsive to the modulating of said carrier to effect movement ofsaid switch to closed position.

4. Synchronizing means comprising a rst relay, means momentarilyactuatable at regular time intervals to energize said relay for closing,a second relay, a third relay, a motor, a source of current connected tosaid motor, a resistor in series with said source to cause said motor torun at a reduced speed, said third relay being energizable to shunt saidresistor and thereby cause said motor to run at a predetermined normalspeed, a battery, a first circuit connecting said first relay, and saidsecond relay and said third relay in circuit with said battery for mo.-mentary energization of said second relay and said third relay uponmomentary energization of said first relay, a normally closed switch, asecond circuit connecting said battery with said switch and second relayand said third relay to provide a holding circuit for said second andthird relay upon momentary energization of said irst relay, and meansdriven. by said motor to effect opening of said switch and the openingof said second circuit.

5. synchronizing means comprising a first relay, means momentarilyactuatable at regular time intervals to energize said relay for closing,a motor, a source of current connected to said motor, a resistor inseries with said source radio I to cause said motor to run at reducedspeed, a switch having an arm movable to closed position to shunt saidresistor and thereby cause said motor to run at a predetermined normalspeed means driven by said motor to move said arm to open position,means to latch said arm in open position, a second relay, a battery, acircuit connecting said second relay and said battery with said firstrelay, said circuit being closable upon energization of said first relayto effect release of said switch arm.

6. synchronizing means comprising a radio transmitter to transmit anormally sustained carrier, means actuatable momentarily and at regulartime intervals to modulate said carrier, a radio receiver, a relayconnected to said receiver and normally biased towards closing positionby said carrier, said relay being arranged actuatable to closed positiononly upon the modulating of said carrier, a motor, a source of currentconnected to said motor, a resistor in series with said source to causethe motor to run at reduced speed, a switch movable to closed positionto shunt said resistor to cause said motor to 'run at a predeterminednormal speed, means driven by said motor to eect opening of said switch,and means responsive to the closing of said relay to effect movement ofsaid switch to closing position.

7. synchronizing means comprising a motor, a source of current connectedto said motor, a resistor in series with said source to cause the motorto run at reduced speed, a switch closable to shunt said resistor tocause said motor to run at a predetermined normal speed, said switchincluding a follower, a cam driven by said motor to engage said followerwhen said switch is in closed position to thereby move said switch toopen position, means to hold said switch in open position, and meansmomentarily actuatable at regular time intervals to release said switchfor movement to closed position.

' 8. synchronizing means comprising a motor, a source of currentconnected to said motor, a resistor in series with said source to causethe motor to run at a reduced speed, a rst electromagnetic switchenergizable to shunt said resistor to cause the motor to run at apredetermined normal speed, a switch including an arm normally incircuit-closing position and with the arm including a follower, a camdriven by said motor and engageable with said follower to open saidswitch, a second electromagnetic switch energizable to effect closing ofsaid first electromagnet switch, said normally closed switch arm beingin series with said second electromagnetic switch, means momentarilyactuatable at regular time intervals to energize said secondelectromagnetic switch, and means including said second electromagneticswitch actuatable upon momentary energization of said secondelectromagnetic switch to maintain said first electromagnetic switchenergized until said switch arm is moved by said cam to open position.

9. synchronizing means comprising a source of current, a first motorconnected to said source, a resistor in series with said motor to causethe motor to run at reduced speed, a switch closable to shunt saidresistor to cause the motor to run at a predetermined normal speed, saidswitch including an arm having a follower, cam means driven by saidfirst motor engageable with said follower to open said switch, means tothereupon hold said arm in open position, electromagnetic meansenergizable to release said arm for movement to closing position, asecond motor, and means driven by said second motor actuatable tomomentarily and at regular time intervals effect energization of saidelectromagnetic means.

l0. synchronizing means comprising a radio transmitter to normally emita sustained carrier, means connected with said transmitter to modulatethe carrier momentarily and at regular time intervals, said meansincluding a rst switch arm carrying a rst follower, a rst revolvable camhaving a first element engageable with said follower once per revolutionof said cam to close said switch, and a rst motor in driving connectionwith said cam, means to effect running of said motor at a predeterminedconstant speed, radio receiving means, a source of current, a secondmotor connected to said source, a resistor in series with said motor tocause the motor to run at reduced speed, circuit means normally shuntingsaid resistor to cause the motor to run at a predetermined normal speed,said circuit means including a second switch arm carrying a secondfollower, a second revolvable cam driven by said second motor and havinga second element thereon engageable with said second follower once perrevolution of said second cam to open said circuit means, and relaymeans connected with said receiving means and energizable in responseonly to the modulated carrier operable to close said circuit means for aperiod of time responsive to the phase position of said second elementat the moment of energization of said relay means.

1l. Synchronizing means comprising a first motor at a radio transmittingstation, power source means connected to said motor to effect operationof said motor at a predetermined constant speed of operation, radiotransmitting means to transmit a normally sustained carrier, meansconnected momentarily actuatable by said rst motor at regular timeintervals to modulate the carrier at audio frequencies, a second motorat a receiving station, a source of current, circuit means connectingsaid source of current with said second motor, radio receiving means atsaid receiving station, means including said radio receiver meansconnected responsive to the modulated carrier to condition said circuitmeans to effect operation of said second motor at a predetermined normalspeed, and means connected actuatable by said second motor to conditionsaid circuit means to cause said motor to run at a speed less thannormal.

12. synchronizing means comprising radio transmitting means to transmita normally sustained carrier, means to momentarily modulate said carrierat regular time intervals, a source of current, a motor, circuit meansconnecting said motor to said source to effect operation of said motorat one predetermined speed, radio receiving means, and means includingsaid radio receiving means connected operable to condition said circuitmeans to eifect operation of said motor at another predetermined speedin response to the modulated carrier.

HENRY MYERS.

